Summer is a busy season for the construction industry, as professionals attempt to combat Finland's deplorable mould situation by renovating temporarily empty schools.
Immediately after students vacated the Vuorentaka school in Hämeenlinna for their summer break in June, builders marched in to fight the damp. Fixing a total of eight schools in the area will rack up some 26 million euros in expenses.
"Summer is a common time for school renovations, but the current mould problems mean that as many schools as possible are now essentially construction sites," Hämeenlinna city education director Mika Mäkelä says.
Project chief Hannu Uutela from property service firm Tekme says that working in the summer is easier and quicker than usual.
"With the school empty of children and staff, we get things done at least twice as fast," Uutela says.
Extent unknown, massive bill
Nobody actually knows just how many Finnish schools there are where the indoor air quality is so poor that renovations are necessary. Not all structures even can or ought to be fixed because of the severity of the problems.
Yle conducted a survey together with the University of Helsinki and the Institute of Occupational Health in early 2016. Based on replies from about one third of Finnish primary schools, some 200-400 school buildings have problems with mould, dampness or other factors affecting the air breathed in daily by students and staff.
Estimates of the actual costs of the much-needed renovations are all over the board, with no specific official figures available.
Parliament published a report back in 2012 that put the expenses of fixing all problematic Finnish schools and kindergartens at between 212 and 318 million euros – however, the Association of Finnish Local and Regional Authorities says the real cost would be closer to 3 billion euros (including regular renovations not based solely on mould trouble).
The parliamentary report estimates that society pays out some 500 million euros every year due to health problems and construction costs stemming from damp and mouldy buildings. The report also says that the bill may well rise if adequate measures are not taken.